Kortz, who was asleep, did not know how the thieves could transport so many birds from her home in the middle of the night without making a sound

"That's what's bothering me, and really bothering my husband. We're not sure," she said. "I'm missing a few breeder cages. If you have a bunch of birds in a cage, they're going to have broken legs and broken wings.

"That's the part that's bothering us the most, the health and well-being of the birds."

Kortz said only four birds remained when she went to check Tuesday morning. Of those four birds, one died Tuesday afternoon, and another died Thursday morning.

The Lee County Sheriff's Department said there were no leads in their investigation as of this morning.

"The damndest part is we've been doing this for 20 years and haven't had a day off," Kortz said. "Because when you've got babies, you have to hand feed them anywhere between every two hours to two to three times a day."

But bird theft is not uncommon in South Florida, said Fred Smith, the Florida, Puerto Rico and Virgin Islands regional director of the American Federation of Aviculture.

"About 10 years ago, this was happening every week in the south half of Florida. Groups of guys were going around stealing all the aviaries," he said.

Smith said the thieves gas the birds when they are asleep, then cut into the cages and take the birds by transporting them in burlap sacks.

"When something like this happens, it makes all of us take notice," Smith said. "We don't look at our aviaries from the eyes of a thief."

Smith said he suspects the resurgence in bird theft comes as a result of the poor economic climate.

"They can steal a $10,000 bird and go offer it for $2,000," he said. "Unless someone knows it's smuggled, [people] take the deals."

Smith said breeding birds is popular in the South Florida region. Prospective breeders can apply for a license with Florida Fish and Wildlife Conservation Committee. The license fee is $50 a year per aviary.

Kortz says she is "overwhelmed and exhausted" by the ordeal.

"The part that hurts is that I'm 69, my husband's 72," she said. "The birds were going to be our retirement, but not anymore."